TY - JOUR
T1 - The Simons Observatory
T2 - Magnetic Sensitivity Measurements of Microwave SQUID Multiplexers
AU - Vavagiakis, Eve M.
AU - Ahmed, Zeeshan
AU - Ali, Aamir
AU - Arnold, Kam
AU - Austermann, Jason
AU - Bruno, Sarah Marie
AU - Choi, Steve K.
AU - Connors, Jake
AU - Cothard, Nicholas
AU - Dicker, Simon
AU - Dober, Brad
AU - Duff, Shannon
AU - Fanfani, Valentina
AU - Healy, Erin
AU - Henderson, Shawn
AU - Ho, Shuay Pwu Patty
AU - Hoang, Duc Thuong
AU - Hilton, Gene
AU - Hubmayr, Johannes
AU - Krachmalnicoff, Nicoletta
AU - Li, Yaqiong
AU - Mates, John
AU - McCarrick, Heather
AU - Nati, Federico
AU - Niemack, Michael
AU - Silva-Feaver, Maximiliano
AU - Staggs, Suzanne
AU - Stevens, Jason
AU - Vissers, Mike
AU - Ullom, Joel
AU - Wagoner, Kasey
AU - Xu, Zhilei
AU - Zhu, Ningfeng
N1 - Funding Information:
Manuscript received November 27, 2020; revised February 16, 2021; accepted March 20, 2021. Date of publication March 29, 2021; date of current version May 14, 2021. This work was supported in part by the Simons Foundation under Award 457687, B.K., and in part by NSF Grant AST-1454881. The work of Steve K. Choi support from the Cornell Presidential Postdoctoral Fellowship and NSF under Award AST-2001866. The work of Zhilei Xu is supported by the Gordon and Betty Moore Foundation. (Corresponding author: Eve M. Vavagiakis.) Eve M. Vavagiakis, Steve K. Choi, Nicholas Cothard, Duc-Thuong Hoang, Yaqiong Li, Michael Niemack, and Jason Stevens are with Cornell University, Ithaca, NY 14853 USA. Zeeshan Ahmed and Shawn Henderson are with the Kavli Institute for Particle Astrophysics and Cosmology, Menlo Park, CA 94025 USA and also with the SLAC National Accelerator Laboratory, Menlo Park, CA 94025 USA. Aamir Ali is with the University of California, Berkeley, CA 94720 USA. Kam Arnold and Maximiliano Silva-Feaver are with the University of California San Diego, La Jolla, CA 92093 USA. Jason Austermann, Jake Connors, Brad Dober, Shannon Duff, Gene Hilton, Johannes Hubmayr, John Mates, Mike Vissers, and Joel Ullom are with NIST Quantum Sensors Group, Boulder, CO 80305 USA. Sarah Marie Bruno, Erin Healy, Heather McCarrick, Suzanne Staggs, and Kasey Wagoner are with Princeton University, Princeton, NJ 08544 USA. Simon Dicker and Ningfeng Zhu are with the University of Pennsylvania, Philadelphia, PA 19104 USA. Valentina Fanfani and Federico Nati are with the University of Milano - Bicocca, 20126 Milano, Italy. Shuay-Pwu Patty Ho is with Stanford University, Stanford, CA 94305 USA. Nicoletta Krachmalnicoff is with the International School for Advanced Studies (SISSA), 34136 Trieste, Italy. Zhilei Xu is with the University of Pennsylvania, Philadelphia, PA 19104 USA and also with the MIT Kavli Institute, Massachusetts Institute of Technology, Cambridge, MA 02139 USA. Color versions of one or more figures in this article are available at https: //doi.org/10.1109/TASC.2021.3069294. Digital Object Identifier 10.1109/TASC.2021.3069294
Publisher Copyright:
© 2002-2011 IEEE.
PY - 2021/8
Y1 - 2021/8
N2 - The Simons Observatory (SO) will be a cosmic microwave background (CMB) survey experiment with three small-aperture telescopes and one large-aperture telescope, which will observe from the Atacama Desert in Chile. In total, SO will field $\sim$70,000 transition-edge sensor (TES) bolometers in six spectral bands centered between 27 and 280 GHz in order to achieve the sensitivity necessary to measure or constrain numerous cosmological quantities. The SO Universal Focal Plane Modules (UFMs) each contain a 150 mm diameter TES detector array, horn or lenslet optical coupling, cold readout components, and magnetic shielding. SO will use a microwave SQUID multiplexing ($\mu$MUX) readout at an initial multiplexing factor of $\sim$1000; the cold (100 mK) readout components are packaged in a $\mu$MUX readout module, which is part of the UFM, and can also be characterized independently. The 100 mK stage TES bolometer arrays and microwave SQUIDs are sensitive to magnetic fields, and their measured response will vary with the degree to which they are magnetically shielded. We present measurements of the magnetic pickup of test microwave SQUID multiplexers as a study of various shielding configurations for the Simons Observatory. We discuss how these measurements motivated the material choice and design of the UFM magnetic shielding.
AB - The Simons Observatory (SO) will be a cosmic microwave background (CMB) survey experiment with three small-aperture telescopes and one large-aperture telescope, which will observe from the Atacama Desert in Chile. In total, SO will field $\sim$70,000 transition-edge sensor (TES) bolometers in six spectral bands centered between 27 and 280 GHz in order to achieve the sensitivity necessary to measure or constrain numerous cosmological quantities. The SO Universal Focal Plane Modules (UFMs) each contain a 150 mm diameter TES detector array, horn or lenslet optical coupling, cold readout components, and magnetic shielding. SO will use a microwave SQUID multiplexing ($\mu$MUX) readout at an initial multiplexing factor of $\sim$1000; the cold (100 mK) readout components are packaged in a $\mu$MUX readout module, which is part of the UFM, and can also be characterized independently. The 100 mK stage TES bolometer arrays and microwave SQUIDs are sensitive to magnetic fields, and their measured response will vary with the degree to which they are magnetically shielded. We present measurements of the magnetic pickup of test microwave SQUID multiplexers as a study of various shielding configurations for the Simons Observatory. We discuss how these measurements motivated the material choice and design of the UFM magnetic shielding.
KW - Magnetic field dependence
KW - SQUIDs
KW - microwave multiplexing
KW - supercondcuting detectors
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U2 - 10.1109/TASC.2021.3069294
DO - 10.1109/TASC.2021.3069294
M3 - Article
AN - SCOPUS:85103775884
VL - 31
JO - IEEE Transactions on Applied Superconductivity
JF - IEEE Transactions on Applied Superconductivity
SN - 1051-8223
IS - 5
M1 - 9388904
ER -